000 00369 a2200097 4500
020 _a9261019315
920 _a92-61-01931-5
245 0 _aCCITT GAS 9 Economic and Technical Aspects of the Transition from Analogue to Digital Telecommunication Networks /
_c.
710 2 _aInternational Telecommunication Union.
_eWydawca
_4pbl
260 _aGeneva :
_bITU,
_c1984.
300 _a168 s.:
_bil.;
_c30 cm.
999 _c1828
_d1828